The invention relates generally to the art of climatic control systems, and more particularly to improvements in reverse cycle heat pumps for both heating and cooling recirculated room air.
The present invention is particularly beneficial in commercial and industrial installations, such as food markets, convenience stores, restaurants, warehouses and manufacturing or processing facilities and the like having primary refrigeration systems to provide multiple refrigeration needs as for cooling low and normal temperature display and storage fixtures, or product cases or zones. The air within such a market or warehouse facility is generally circulated and heated or cooled to maintain a comfortable environment, and this recirculation and temperature (and humidity) conditioning of air is conventionally handled by apparatus completely separate from and independent of the primary commercial or industrial refrigeration system.
In the past, numerous climatic control systems have been designed to provide selective cooling (air conditioning) and heating of recirculated air, and in recent years it has become a prevalent practice to incorporate an auxiliary refrigeration system condenser or heat reclaim coil that is physically located in an air heating duct and selectively connected to the main refrigeration system compressors in order to reclaim and use some of the heat of condensation as an air heating medium thus meeting some of the environmental heating requirements of the store. It is recognized that such reclaimed heat would normally be lost to the ambient in an outside condenser of a conventional commercial refrigeration system, and thus some valuable energy and cost savings are realized by reclamation of this heat for store heating purposes. It is also recognized generally that such reclaimed heat is totally inadequate for major heating days during the winter and some form of supplemental heating is required, and various systems have been used including reverse cycle heat pumps. Such heat pumps normally provide an air conditioning coil in the air ductwork for conventional summer air conditioning, and provide a reverse refrigerant flow path during winter heating so that the same coil will function as a condenser in the same manner as the reheat coil just discussed. However, the arrangements of various components in past climatic control systems have not been energy efficient or utilized the aggregate heating potential of the heat pump and refrigeration system heat reclaim coil.